Introduction: Bevacizumab is a monoclonal antibody against vascular endothelial growth factor. It is widely used in the treatment of metastatic colorectal cancer. It has some specific side effects including severe bleeding, wound healing problems, gastrointestinal perforation, proteinuria and hypertension.
Case presentation: We present the case of a 65-year old Asian man with synovial metastasis of the knee who experienced intraarticular hemorrhage after bevacizumab treatment. He presented with monoarthritis of the left knee.
Conclusion: Bevacizumab-related hemorrhage can cause serious morbidity and unusual sites of hemorrhage may be seen.